JP6894836B2 - Optical shape detection for instrument tracking in orthopedics - Google Patents

Description

The disclosure relates to medical devices, and more specifically to shape detection of optical fibers in medical applications for tracking medical devices during computer-assisted procedures.

Computer-assisted surgery (CAS) systems are used for preoperative planning and intraoperative surgical navigation. In this context, preoperative planning is a computer-assisted decision for surgical steps such as amputation, incision, and targeting. Planning can be done before or during the procedure. Intraoperative planning is often one of the medical imaging modalities (computed tomography (CT), magnetic resonance imaging (MRI), ultrasound, X-rays, endoscopy. Use 2D or 3D images of the patient using an anatomical model (eg, a knee model) or an examination, etc.). In the context of CAS, surgical navigation is the live tracking of instruments and patient anatomy that allows the surgeon to perform preoperative planning accurately. Surgical navigation is performed using tracking techniques.

An example of a tracking technique is line-of-sight optical tracking. The line-of-sight optical tracking technique uses an optical camera that operates in either the visible or infrared range. The camera is configured to detect markers within its field of view and infer the position and orientation of the marker placement based on their relative positions. Generally, two or more cameras arranged in a known configuration are used to enable stereoscopic vision and perception of depth. This tracking technique requires an uninterrupted line of sight between the cameras (s) and the markers.

Total knee arthroplasty requires removal of the femur and tibia and replacement with an implantable prosthesis. Using CAS in total knee arthroplasty, a preoperative planning module is used to plan the appropriate amputation surface and to track the bone and instrument during the procedure to enable execution of the plan. Bone is often excised using a cutting block that guides the cut surface to the correct position and angle to receive and align the implanted prosthesis. CAS aims to improve both the position and orientation of the amputation block and subsequent implants in order to restore the joint to optimal biomechanics.

The line-of-sight optical tracking CAS system for total knee arthroplasty includes a set of line-of-sight optical tracking attachments that are attached to the patient to perform anatomical tracking. The line-of-sight optical tracking attachment is firmly attached to the bone by one or more screws and extends a certain distance from the bone. In total knee arthroplasty, these tracking devices are attached to both the femur and tibia for live anatomical tracking.

Existing optical CAS systems have many drawbacks. The line-of-sight optical CAS system requires an unobstructed path between the detection camera and the tracking fixture. Tracking fixtures that cannot be seen from the camera cannot give valid measurements. Maintaining an unobstructed pathway in every part of the procedure can be difficult, especially when manipulating bone to test dynamic biomechanics. Not only do these CAS systems require a line of sight, but they are only highly accurate within the specified volume. This volume is relative to the camera position and can be difficult to maintain throughout the procedure, especially during joint manipulation. To achieve the required accuracy, line-of-sight CAS systems typically use reflective balls placed within an optical tracking fixture that can have a maximum length of up to 20 cm. Such large fittings limit the physical work space available to the clinician and pose a risk of intraoperative collision. Due to the size and weight of the optical tracking attachment, large screw pins are required for strong and accurate bone attachment. In some cases, a single tracking attachment requires two screw pins. These threaded pins can cause adverse effects such as stress damage (especially when two pins are used in close proximity), infection, nerve damage, and pin loosening (causing additional pins or inaccuracies in measurements). There is.

In addition, electromagnetic (EM) navigation systems also have many drawbacks. As with gaze tracking, it can be difficult to maintain an optimal clinical workflow while meeting the requirements of the EM system. The EM system provides accurate measurements only within the volume specified in relation to the position of the magnetic field generator. In addition, the metal in the EM magnetic field can create interference and reduce measurement accuracy.

According to this principle, the optical shape detection system includes a mounting mechanism configured to secure the optical shape detection fiber to an instrument. The optical shape detection fiber is connected to the fixture and is configured to identify the position and orientation of the fixture. The optical shape detection module is configured to receive feedback from the optical shape detection fiber and to align (register) the device in relation to the operating environment. The position response module is configured to provide feedback to the operator based on the position or orientation of the device to guide the use of the device.

Another optical shape detection system includes an optical shape detection module configured to receive feedback from one or more optical shape detection fibers. At least one optical shape detection fiber is connected to one or more instruments, and the optical shape detection fiber is used to track the device in position in relation to the operating environment. The position response module is configured to give feedback to the operator based on the position or orientation of the instrument and guide the use of the instrument based on the surgical plan. Includes an anatomical map of the area of the operating environment. The location of one or more instruments is tracked in relation to the anatomical map.

A method for tracking an instrument using optical shape detection is a step of fixing the optical shape detection fiber to the instrument, which is configured to connect the optical shape detection fiber to the instrument and identify the position of the instrument. The step of aligning the position of the device in relation to the stored image of the operating environment, the step of receiving feedback from the optical shape detection fiber to determine the current position, and the position or orientation of the device. Includes steps to guide the use of the device based on.

These and other objectives, features, and advantages of the present disclosure will become apparent by reading the detailed description of the exemplary embodiments set forth below in association with the accompanying drawings.

The present disclosure presents in detail a description of the preferred embodiments set forth below with reference to the following drawings.

FIG. 6 is a block / flow diagram showing a shape detection system for tracking an instrument in an operating environment according to an embodiment. It is a figure which shows the button type fixing mechanism which has the s-shaped fiber path according to one Embodiment. It is a figure which shows the button type fixing mechanism which has a loop-shaped fiber path according to one Embodiment. It is a figure which shows the button type fixing mechanism which has the linear fiber path embedded in the material according to one Embodiment. It is a figure which shows the 2-split button type fixing mechanism used as a mounting device according to one Embodiment. It is a figure which shows the compatibility of the optical fiber sensor between instruments according to a useful embodiment. It is a figure which shows the alignment between the instrument coordinate system, the photodetection fiber, and the bone coordinate system according to one Embodiment. It is a figure which shows the alignment workflow according to one Embodiment. It is a flow diagram which shows the method for shape detection tracking of an instrument according to an exemplary embodiment.

According to this principle, systems and methods for optical shape detection that can be used to display relative positions of instruments, fixtures, mechanical parts, etc. on anatomical maps or other images during a surgical procedure are provided. To. In one embodiment, the optical shape detection fiber can be attached or mounted inside or on a tool, instrument, fixture, or the like. Optical shape detection measurements can be aligned to the anatomical map. The position of the light shape detection marker with respect to the anatomical map can be displayed to the user. Optical shape detection fibers may be attached to orthopedic instruments or instruments such as drills and cutting rigs to track their position. In addition, optical shape detection may be used to track soft tissues and / or bone in orthopedic procedures. The optical shape detection system can be attached to bone, ligaments, skin, inserts, etc., or a combination thereof.

According to this principle, optical shape detection is used to track an instrument in an orthopedic procedure or other procedure. The optical shape detection fiber (s) can be permanently embedded in the fixture or temporarily attached to the fixture. A method of alignment between an instrument (OSS sensor) equipped with optical shape detection fibers (plural fibers) and a patient coordinate system is also described. The use of light shape detection enabled tools is also described, focusing on intelligent tools that can notify the operator if in the correct position or limit for safety or other purposes.

Optical shape detection (OSS) uses light along a multi-core optical fiber to restore shape along that fiber. A related principle utilizes distribution strain measurements in fiber optics with characteristic Rayleigh backscatter or controlled lattice patterns. The shape along the optical fiber starts at a specific point along the launch or sensor known as z = 0, and subsequent shape positions and orientations are relative to that point. Optical fibers are, for example, 200 microns in diameter and can be up to several meters in length while maintaining millimeter-level accuracy. Optical shape detection fibers can be integrated into a wide range of medical devices to perform live guided medical procedures. As an example, a guide wire or catheter can be used for navigation to the artery with the optical shape detection measurements superimposed on the preoperative image.

According to this principle, an OSS fiber sensor is used that occupies a small area, is lightweight, and can track and integrate shape-detected instruments. Intraoperative tracking of the instrument provides the opportunity to improve the accuracy of implant placement and ultimately improve clinical outcomes. In addition, safety can be improved by ensuring the position recognition of the instrument (especially the cutting instrument) with respect to the patient's anatomy during the operation.

It will be appreciated that the present invention is described with respect to medical devices. However, the teachings of the present invention are much broader and can be applied to any fiber optic appliance. In some embodiments, this principle is used for tracking or analysis of complex biological or mechanical systems. Specifically, this principle is applicable to internal tracking procedures of biological systems and procedures in all areas of the body such as lungs, gastrointestinal tract, excretory organs, and blood vessels. The elements shown in the figure can be implemented in various combinations of hardware and software, and can provide functions that can be combined into a single element or multiple elements.

The functionality of the various elements shown in the figure can be provided by the use of dedicated hardware and hardware that can run the software in association with the appropriate software. When provided by a processor, these features can be provided by a single dedicated processor, a single shared processor, or a plurality of individual processors, some of which can be shared. Moreover, the explicit use of the term "processor" or "controller" is not construed as an exclusive indication of the hardware in which the software can run, and is not limited to digital signal processor ("DSP") hardware. , Read-only memory (“ROM”) for storing hardware, random access memory (“RAM”), non-volatile storage device, etc. can be implicitly included.

Furthermore, all descriptions herein, and specific examples thereof, illustrating the principles, embodiments, and embodiments of the present invention are intended to include both structural and functional equivalents thereof. To. Furthermore, such equivalents are intended to include both currently known equivalents and future developed equivalents (ie, any developed elements that perform the same function regardless of structure). Will be done. Thus, it will be appreciated by those skilled in the art that, for example, the block diagrams presented herein represent conceptual diagrams of exemplary system components and / or circuits that embody the principles of the present invention. Similarly, the various processes represented by any flowchart, flow diagram, etc. are substantially represented in a computer-readable storage medium, whether the computer or processor is explicitly or not. It will be acknowledged that it can be run by any computer or processor.

Further, embodiments of the present invention take the form of computer program products accessible from computer-enabled or computer-readable storage media that provide program code used by or in connection with a computer or any instruction execution system. be able to. For the purposes of this description, a computer-enabled or computer-readable storage medium contains, stores, transmits, propagates, and contains programs used by or in connection with an instruction execution system, instruction execution device, or instruction execution device. Or it can be any device that can be transferred. The medium may be electronic, magnetic, optical, electromagnetic, infrared, or a semiconductor system (or device or device) or propagation medium. Examples of computer-readable media include semiconductor or solid-state memory, magnetic tape, removable computer diskettes, random access memory (RAM), read-only memory (ROM), rigid magnetic disks, and optical disks. Current examples of optical discs include compact disc-read-only memory (CD-ROM), compact disc-read / write (CD-R / W), Blu-ray ™, and DVD.

Here, referring to a drawing in which similar numbers represent the same or similar elements, first looking at FIG. 1, the optical shape in an orthopedic application and another application using a shape detection compatible device according to one embodiment. A system 100 for detection guidance is shown exemplary. System 100 may include a workstation or console 112 from which actions are supervised and / or managed. The workstation 112 preferably includes one or more processors 114 and a memory 116 for storing programs and applications. The memory 116 can store a photodetection module 115 configured to interpret an optical feedback signal from the shape detection device or system 104. The light detection and interpretation module 115 uses optical signal feedback (and any other feedback, such as electromagnetic (EM) tracking) to position bones or joints and other anatomical features, such as skin. , Ligaments, tendons, muscles, and other substances or tissues that are configured to restore position-related deformities, distortions, and other changes.

The shape detection system 104 includes one or more optical fiber sensors 102. Each sensor 102 includes an optical fiber 126 configured in one or more configuration patterns. The optical fiber 126 is connected to the workstation 112 via a start point mount 125 and cable wiring 127. Cable wiring 127 may optionally include optical fiber, electrical connections, other appliances and the like. The cabling 127 interfaces with an optical query unit 108 that includes or can work with one or more light sources 106. The optical query unit 108 transmits and receives an optical signal from the shape detection system 104. The operating room rail 124 includes a start point mount 125 that includes a reference point or start point (z = 0) for one or more photosensors 102.

The shape detection system 104 using an optical fiber may be based on an optical fiber Bragg lattice sensor. A fiber optic Bragg grating (FBG) is a short segment of fiber that reflects a particular light wavelength and transmits everything else. This is achieved by adding periodic variations to the index of refraction of the fiber core to create a wavelength-specific dielectric mirror. Therefore, the Fiber Bragg grid can be used as an in-line optical filter that blocks certain wavelengths, or as a wavelength-specific reflector.

The inherent backscattering of conventional optical fibers can be utilized for optical shape detection (OSS). One such technique uses Rayleigh scattering (or other scattering) in standard single-mode communication fibers. Rayleigh scattering occurs as a result of random fluctuations in the index of refraction within the fiber core. These random fluctuations can be modeled as Bragg grids with random amplitude and phase fluctuations along the grid length. By using this effect with three or more cores extending into one multi-core fiber, the 3D shape and dynamics of the target surface can be tracked.

Also available for OSS are Fiber Bragg gratings (FBGs) that use Fresnel reflections at each interface where the index of refraction changes. At some wavelengths, the reflected light of different periods is in phase, so there is constructive interference in the reflection and, as a result, canceling interference in the transmission. Bragg wavelengths are sensitive to strain as well as temperature. This means that the Bragg grid can be used as a detection element for fiber optic sensors. For FBG sensors, the measured quantity (eg, strain) causes a shift in Bragg wavelength.

One advantage of OSS is the ability to disperse various sensor elements over the length of the fiber. By combining various sensors (gauges) along the length of the fiber embedded in the structure with three or more cores, it is possible to determine the three-dimensional form of such a structure with high accuracy and precision. Become. A large number of FBG sensors can be positioned at various positions along the length of the fiber. From the strain measurement value of each FBG, the curvature of the structure at that position can be estimated. The overall three-dimensional morphology is determined from a number of measurement positions.

In one embodiment, one or more optical sensors 102 are connected to one or more appliances 128. Instrument 128 may include a number of different categories of devices, tools, fixtures, fixtures and the like. For example, a number of different instruments 128 can be used during orthopedic surgery. These appliances 128 can be broadly divided into two categories. For example, one held by a surgeon or operator and one physically attached to a patient or subject 160. For purposes of illustration, examples of such instruments 128 that can be attached to a patient include cutting blocks, jigs, screws, pins, trial implants, and the like. Examples of such instruments 128 that can be held by hand by a surgeon or operator include alignment pointers, bone drills, bone saws, osteomes (as well as only), scalpels, forceps, aspirators, etc. Be done. In some embodiments, the instrument 128 may include a probe, an endoscope, a robot, an electrode, a drill, a cutting tool, or other medical component.

In a particularly useful embodiment, the OSS fiber sensor 102 can be attached to the appliance (s) 128 in a number of ways. For example, the attachment of the fiber sensor 102 can be permanent. For instruments such as bone drills or bone saws, it may be desirable to permanently attach or embed a dedicated OSS fiber sensor 102 in the instrument 128. The fiber sensor 102 can be placed in the appliance 128 via, for example (if available) an electrical cable, or other accessory. The fiber sensor 102 can be terminated within the handle of the instrument 128 or within the instrument tooltip. Alternatively, the installation of the fiber sensor 102 may be temporary. For appliances such as osteomes or cutting blocks, it may not be desirable or cost effective to permanently attach the fiber sensor 102 to the appliance 128. An alternative to permanent mounting is a feature (s) on the instrument 128 to which the OSS fiber sensor 102 can be temporarily attached. Such an embodiment has a mounting mechanism 130 having two or more fitting mounting points 134, 136, one at the distal end of the OSS tether and the other on the instrument.

On the instrument side, the attachment point 136 can be an integral part of the instrument design, or can be retrofitted or attached by screws, fasteners, glue, or similar mechanisms. Attachment points 134 on the fiber sensor 102 can be attached to and detached from attachment points 134 on the instrument 128 using temporary fixing methods such as magnets, clasps, and snap fasteners. The mounting mechanism 130 preferably includes an interface between mounting points 134 and 136 for mounting only in a particular direction (ie, only in one direction) to ensure that the correct orientation of the appliance 128 is known.

The workstation 112 receives feedback from the shape detection system 104 and is configured to record position (and orientation) data about where one or more photosensors 102 were in the volume 131 image generator module 148. including. An image 135 of one or more optical sensors 102 in the space or volume 131, or a virtual representation of the device 128 to which the fiber is attached, can be displayed on the display device 118. The workstation 112 includes a display 118 for viewing an internal image of the subject (patient) or volume 131, and includes an image 135 as an overlay on the image collected by the imaging device 110 or as another rendering of the detection device 104. obtain. The imaging device 110 may include any imaging system (eg, computed tomography (CT), ultrasound, fluoroscope, magnetic resonance imaging (MRI), etc.). The display 118 also allows the user to interact with workstation 112 and its components and functions, or any other element within system 100. This is made even easier by the interface 120. Interface 120 includes a keyboard, mouse, joystick, tactile device, or any other peripheral or control device that allows user feedback from workstation 112 and interaction with workstation 112.

The system 100 can be used to display the position of the instrument 128 overlaid on an anatomical map 137 (eg, an anatomical image of volume 131) during a surgical procedure or otherwise based on optical shape detection. .. The system 100 includes integrating the optical shape detection fiber 102 into an instrument 128 that can be contrasted with the anatomical position of the patient 160 (eg skin, muscles, ligaments, bones, etc.). By aligning the light shape detection sensor 102 with the anatomical map 137 and displaying the positions (plural positions) of the light shape detection sensor 102 and thus the instrument 128 connected to it, the permissible limit and the user It can warn and warn of potential damage and out-of-range operation as indicated by planning or other criteria.

The optical sensor 102 may have one or more reference positions, a global coordinate system, or their own coordinate system aligned with any other coordinate system. The optical shape detection fibers 102 are aligned with each other using a number of techniques, including shape-to-shape registration, mechanical alignment of the starting point, point-based alignment, and the like. Can be done. Measurements can be provided in association with the anatomical map 137 to make the shape detection measurements useful to the clinician. The anatomical map can be a preoperative image (eg CT, MRI, fluoroscope, or ultrasound image) or an intraoperative image (eg live). In some cases, the anatomical model is morphed during the alignment step to match feature measurements. As used herein, a 3D surface or volume obtained preoperatively or from any source is referred to as a model.

Once the optical shape sensing fiber 102 is placed and aligned on an anatomical map or other reference (eg bone 138), the fiber position can be displayed in relation to the operator (eg on display 118). The display of OSS data on an anatomical map can take many forms and provide multiple functions.

The system 100 makes it possible to place instruments 128, such as cutting and drill guides, and instruments that generate the required cuttings and holes, with greater accuracy. However, knowing the position and orientation of the device 128 also makes it possible to add more "intelligent" functionality. In one example, the position response module 144 provides automatic control of the cut surface. When using a shape-sensing cutting instrument such as a bone drill or a bone saw, the drill bit or saw blade can be actively stopped based on the known position of the cut surface with respect to the patient's anatomy. The speed or other function of the device may be changed according to its position. In one embodiment, the surgeon can indicate a virtual "safety zone" in which the cutting instrument is automatically turned off or the operation of the instrument is changed.

The position response module 144 is configured to provide the operator with feedback based on the position or orientation of the device to guide the use of the device 128. The position response module 144 controls instrument function based on the instrument position associated with the zone identified in the operating environment, provides feedback to the operator when the instrument is positioned in a particular orientation or location, and instrument position. It may be configured to stop the use of the device when the device changes, or to start the function of the device when the position of the device changes. Feedback given to the user includes, for example, auditory, visual, tactile, etc., and is given via an output device 150 located on the console 112 of the instrument 128, or other, such as via an interface 120, a display 118, etc. Can be given in a way.

In another example, the module 144 can provide operator feedback (eg, auditory, visual, tactile, etc.) (via instrument 128) when the instrument is positioned in the correct orientation. Correctly setting the position and orientation of the instrument 128 is an important parameter for ensuring correct implant placement or other tasks. For this reason, cutting and drill guides are customarily used. As an additional input for the surgeon, if the position and orientation of the handheld instrument 128 is within the desired position threshold, the system uses auditory, visual, tactile or tactile feedback (eg, interface 120 or instrument 128). The operator can be alerted (via). In yet another example, the control module 144 may be used to detect contact between the instrument and the bone. In embodiments where the OSS fiber sensor 102 is permanently embedded within the instrument 128, the integration can be designed so that contact with the instrument bone is detected. Such embodiments are particularly suitable for alignment devices used as part of the initial point-based alignment (ie, alignment pointer). Such embodiments can also be used to detect the force of contact force between the instrument and the bone.

In yet another example, the control module 144 may be used to perform cutting or automatic positioning of the drill guide. Mechatronically (eg, mechanically and electronically) operated cutting guides (128) can be used that are aligned with the patient and can automatically set the optimal cutting surface based on preoperative planning. it can. This replaces the cutting and completely manual adjustment of the drill guide to the required position. These traditional manual adjustment steps are performed after the cutting guide is first attached to the bone and have a very limited range of motion.

This principle applies to any use of optical shape sensing fibers for surgical guides and navigation. In a particularly useful embodiment, the principle can be used in knee replacement, anterior cruciate ligament (ACL) repair, hip replacement, brain surgery, elbow surgery, and other such applications. In addition, OSS can utilize any type of reflection or scattering phenomenon, such as (enhanced and usually) Rayleigh scattering, as well as fiber Bragging of shape-sensing fibers. This principle can be used with manual and robotic navigation systems.

With reference to FIGS. 2A to 2C, a configuration example for attaching the optical fiber for optical shape detection to the attachment mechanism 130 (for example, formed from the points 134 and 136) is exemplified. The optical shape detection fiber 126 can be attached to the attachment mechanism 130 by a number of methods. As shown in FIGS. 2A and 2B, mechanical clamping of the fiber optic 126 to the mounting mechanism 130 (the fiber optic coating may or may not be intact) includes a groove or path on which the fiber is placed. obtain. The path may include a predetermined shape, such as the s-shape 210 (FIG. 2A or loop 212 (FIG. 2B)). In the example of FIG. 2C, the straight portion 214 of the fiber is embedded in the material 216 of the mounting mechanism 130, and the curved portion is freely deformable in the space surrounding the mounting mechanism 130. Any other shape of the embedded fiber can also be used (eg, other than loop 212 or s-shape 210).

The fiber 126 may be connected to the attachment mechanism 130 using an adhesive or clamp on the fiber optic 126 (the fiber optic coating may or may not be intact). Alternatively, free-floating fiber 126 may be passed through an optically traceable (shape-detected) known shape. Combinations of these and / or other mounting modes are also envisioned.

In one embodiment, the optical fiber 126 is permanently attached to the attachment mechanism 130. In another embodiment, the mounting mechanism 130 can be split so that half of the mounting mechanism 130 is permanently attached to the fixed portion and the other half is attached to the OSS tether (fiber 126). ..

With reference to FIG. 3, the bifurcated mounting mechanism 130 can be split and the clinician can connect and disconnect the mating mounting points 134 and 136 as needed. This allows the clinician to attach or join the two halves 134, 136 at the appropriate points during the procedure. The mating attachment points 134, 136 are preferably joined (eg, keyed) in only one particular orientation using the mating machine portion 140. Connections at mating attachment points 134 and 136 can be achieved using fasteners (not shown) such as clips, clasps, screws, magnets and the like. This bifurcated button configuration allows one OSS tether (fiber 126) to be used in many ways during the procedure, eg, attaching the fiber to various mating attachment points 134 on the appliance 128. Can be done.

With reference to FIG. 4, according to this principle, the fiber optic sensor 102 may be configured to be able to perform detachment and connection to a plurality of different instruments 128. Each appliance 128 features a mounting point 202 configured to receive a mating portion 213 of the fiber optic sensor 102. FIG. 4 schematically illustrates a bone drill 204 and a cutting block 206 used in an orthopedic procedure. The optical fiber sensor 102 features a fitting portion 213 at its distal end. The fiber optic sensor 102 can be manually moved between instruments (204, 206).

One advantage of such a temporary mounting scheme is that the number of OSS consoles required can be minimized by switching a single fiber sensor 102 between many different instruments during the course of the procedure. In additional embodiments, a single fiber optic sensor 102 with multiple attachment points 202 along its length may be used. In such an implementation, one fiber sensor 102 can track several instruments at the same time.

With reference to FIG. 5, four coordinate systems that can be aligned together are illustrated exemplary, and three alignments that can be performed to track the instrument 128 within the bone coordinate system are illustrated. The three alignments are the alignment 310 from the instrument coordinate system 306 to the instrument OSS sensor coordinate system 302, the alignment 312 from the instrument OSS sensor coordinate system 302 to the bone OSS sensor coordinate system 304, and the alignment 312 from the bone OSS sensor coordinate system 304 to the bone. Includes alignment 314 with respect to coordinate system 308.

The instrument coordinate system 306 is aligned with the OSS sensor 302 that tracks the instrument. This can be detected by executing (a-priori) in advance using, for example, a reference table. Instrument and bone tracking OSS sensors can be aligned in many ways (eg, shape-by-shape alignment, point-based alignment, or, in the simplest case, known mechanical transformations between their origins. ). The bone coordinate system 308 is aligned with the OSS sensor 302 that tracks the bone using, for example, a knee body target. Once the three alignments 310, 312, 314 have been performed, the instrument is aligned with the bone.

Looking at FIG. 6 with reference to FIG. 5, an exemplary workflow of alignment of the appliance 128 and the fiber optic sensor 102 is shown. This workflow can be divided into multiple operating regions such as pre-402 and operating theater 412. At block 404, a test fiber optic sensor can be attached to the instrument. At block 406, the instrument to which the sensor is attached is placed within the alignment fixture. The alignment fixture may include a known position for testing or initializing the alignment of the sensor and the instrument. At block 408, alignment can be verified and conversion between the instrument coordinate system (306) and the sensor coordinate system (302) can be performed. As a result, the alignment 310 is performed. In block 410, the verified alignment transformation is saved in, for example, reference table 426. The first conversion can be generated depending on the type of instrument or mounting device. Reference table 426 indexes the device identification (device ID) data and the corresponding transformations used, as described below. A reference table 426 or similar memory structure can be used to maintain alignment between the instrument (128) and the sensor (102). The exact conversion of each instrument to the fiber mounting point is generated separately and accessible within the OSS user interface. It is also possible to place the alignment fixture in the operating room 412 in the field for live alignment between the sensor (102) and the instrument (128).

Alignment 310 of the instrument coordinate system (306) with respect to the instrument OSS sensor coordinate system (302) may include permanently attaching / integrating the sensor (102) to the instrument (128). In this case, it is necessary to align the sensor in relation to the device at the time of integration or attachment to the device. This can be done by placing the instrument (128) together with the sensor (102) in the alignment fixture. This fixture can be, for example, a mold for an instrument, or a dynamic fixture (such as a pivotal fixture) that moves the instrument by a known technique to provide appropriate conversion. In another embodiment, the reattachable sensor (102) is placed on the instrument (128). In this case, the fiber attachment shall be in a mechanical position and orientation known in relation to the appliance (eg, clamps on the fixture features). In the laboratory, transformations can be generated using representative sensors, instruments, and fixtures. This can also be known mechanically by the design of the fixture. In any case, the conversion is determined and stored.

In the operating room 412, the instrument (128) is selected at block 414. Once a given instrument is activated or selected, members of the operating room staff can select the appropriate instrument from the library. Alternatively, radio frequency identification (RFID) or similar device identification methods can be used to perform automatic detection of the correct instrument. At block 416, the fiber optic sensor (102) is attached to the appliance (128). At block 418, the device type (device ID) is selected by software. At block 420, the software searches the reference table 426 for the corresponding transformation. Alignment 312 and 314 may be performed using this information.

When the alignment with respect to the bone is preferable, the alignment 312 of the instrument OSS sensor coordinate system 302 with respect to the bone OSS sensor coordinate system 304 may be performed. An OSS tracking device can be used in conjunction with OSS tracking of the bone itself, allowing all elements to be aligned in one coordinate system. This can be easily achieved by ensuring that the starting point fixtures of the bone-tracking fibers (s) and the instruments-tracing fibers (s) are fixed in a known geometric relationship. If they are not in known geometric relationships, alignment between shape coordinate systems can be achieved by point-based or shape-by-shape alignment. In the case of the single sensor method, the instrument and bone are automatically in the same coordinate system. Alignment 314 of the bone OSS sensor coordinate system 304 with respect to the bone coordinate system 308 can be performed by point-based alignment of the bone target. Other alignment techniques may be used. At block 422, an optional verification step can be performed. This may include holding the instrument tip in a known position and comparing the results.

It will be appreciated that the embodiments described herein use the knee joint exemplary. However, any joint or other anatomical feature, artificial brace, or model may use this principle. In addition, the embodiments described herein may be combined to further enhance the advantages of this principle. For example, sutured OSS fiber embodiments can be combined with skin-attached OSS fibers and / or sleeves can be combined with integrated OSS fibers.

With reference to FIG. 7, a method for tracking an instrument using optical shape detection is exemplified. At block 502, the optical shape detection fiber is fixed to the appliance. The optical shape detection fiber is connected to the fixture and is configured to identify the location of the fixture. The optical shape detection fiber may be mounted so as to be interchangeable with a plurality of appliances.

At block 504, the instrument is aligned with respect to the stored image of the operating environment. The operating environment may include an operating room for medical procedures. The location of the instrument can be tracked in relation to the anatomical map. At block 506, feedback is received from the optical shape detection fiber to determine the position (and orientation) of the appliance. Give information feedback to the user using location information. This information can take many forms. For example, the user may receive a signal that the instrument to be tracked is properly positioned. The user may receive feedback that the device has moved out of range or has left the safety zone. The user may receive feedback on whether or not the device is allowed to be placed within a particular area.

Block 508 can guide instrument function for use or function based on the position of the instrument or the force / strain applied to the instrument. Here, the usage guide means to provide information for expanding or improving the use of the device or for using the device more safely. For example, block 510 controls the instrument based on the position of the device with respect to the zone identified in the operating environment. This may include turning off the equipment when exiting an identified zone, such as a safety zone. In one example, when the appropriate depth is reached, the drill is turned off or a display or sound alert is given. In another embodiment, the instrument can be inserted until the surface is detected, for example until the instrument comes into contact with the bone. The instrument can be started or stopped when the position of the instrument changes, or when the measured force or strain reading exceeds the threshold. The function of the instrument may correspond to a change in position or a measured force or strain.

At block 512, position feedback (eg, physical feedback) can be given to the operator when the instrument is positioned in a particular orientation. For example, if the instruments are properly aligned, indicators such as light, sound, vibration, message, etc. may be given. This also includes adjusting the cutting guides and the like by allowing automatic positioning of the cutting guides along and / or according to a given axis in a given coordinate system.

In interpreting the appended claims, the following should be understood:
a) The word "comprising" does not preclude the existence of any element or act other than those listed in a given claim.
b) The word "a" or "an" immediately preceding an element does not exclude the existence of more than one such element.
c) No reference code in the claims limits their scope.
d) Some "means" may be represented by structures or functions performed by the same item or hardware or software.
e) Unless otherwise instructed, it is not intended that a particular order of conduct is required.

Although preferred embodiments of optical shape detection for instrument tracking in orthopedics (these are intended to be exemplary without limitation) have been described, they may be modified and modified by one of ordinary skill in the art in light of the above teachings. It should be noted that. It will therefore be appreciated that changes contained within the embodiments disclosed herein, outlined in the appended claims, can be made in the particular embodiments disclosed. In particular, the details are described as required by the Patent Law, but those claimed for patent and desired to be protected by a letter certificate are described in the appended claims.

Claims (12)

An attachment mechanism that fixes an optical shape detection fiber that is connected to a medical device and is configured to identify the position and orientation of the medical device to the medical device.
An optical shape that receives an optical signal as feedback from the optical shape detection fiber and aligns the medical device to which the optical shape detection fiber is connected with an anatomical map acquired in an operating room for medical treatment. With the detection module
Hearing the operator based on the position or orientation of the medical instrument, giving the operator feedback of visual or tactile, and position response module to guide the use of the medical instrument,
With
The position response module is an optical shape detection system that provides the operator feedback when the medical device is positioned in a specific orientation. The optical shape detection system according to claim 1, wherein the mounting mechanism includes a removable device that connects to a part of the medical device. The removable device, and connected to the medical device comprises a matable portion for separating from the medical device, the optical shape detection system according to claim 2. The optical shape detection system according to claim 3, wherein the removable device can be interchangeably mounted on a plurality of medical devices. The optical shape detection system according to claim 1, wherein the position response module controls the device function based on the position of the medical device aligned on the anatomical map. The optical shape detection system according to claim 1, wherein the position response module starts or stops the use of the medical device when the position of the medical device changes. An optical shape detection module that is connected to a medical device and receives an optical signal as feedback from one or more optical shape detection fibers configured to identify the position and orientation of the medical device.
With the one or more medical devices to which the one or more optical shape detection fibers are connected,
Hearing the operator based on the position or orientation of the medical instrument, giving the operator feedback of visual or tactile, and position response module to guide the use of the medical instrument on the basis of the surgical plan,
An anatomical map obtained in an operating room for a medical procedure, the anatomical map to which the medical device is aligned, and the anatomical map.
With
The position response module is an optical shape detection system that provides the operator feedback when the medical device is positioned in a specific orientation. It said one or more optical shape detection fiber, said that the medical instrument to be connected and the medical instrument is mounted removably to the one or more medical devices including matable portion for separating claim 7. The optical shape detection system according to 7. The optical shape detection system according to claim 8 , wherein the matable portion can be interchangeably mounted on a plurality of medical devices. The optical shape detection system according to claim 7 , wherein the position response module controls the device function based on the position of the medical device aligned with the anatomical map. The optical shape detection system according to claim 7 , wherein the position response module starts or stops the use of the medical device when the position of the medical device changes. A method for tracking a medical device using an optical shape sensing fiber configured to identify the position and orientation of the medical device.
A step of fixing by connecting the optical shape detection fiber to said medical instrument,
Aligning the anatomical map and the medical device obtained in the operating room for medical treatment,
A step of receiving an optical signal as feedback from the optical shape detection fiber to determine the current position,
A step of giving the operator auditory, visual or tactile operator feedback when the medical device is positioned in a particular orientation.
A method.

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